单项选择题
A.并 B.交 C.投影 D.笛卡尔乘积
A.Dim n,m As Integer,s As String B.Dim a%,b$,c As String C.Dim a As Integer,b,c As String D.Dim x%,y As Integer,z As String
A.x/2=Int(x/2) B.x Mod 2=0 C.Fix(x/2)=x/2 D.x\2=0